1. The Field of the Invention
The present disclosure relates generally to trailer hitch systems, and more particularly, but not necessarily entirely, to a bracket system for trailer hitch systems for reducing trailer sway and/or equalizing the weight of the trailer.
2. Description of Related Art
Various different types of trailer hitches are known in the art for attaching trailers to towing vehicles. One of the most common types of towing systems utilizes a ball hitch. Typical ball hitches have a generally spherical shaped ball with a stem or threaded rod extending from a base of the ball. The threaded rod may be configured to engage a hitch head mounted on the towing vehicle using a threaded receiver or ball hitch fitting. A trailer coupling member, positioned on a front of the trailer tongue, may engage the ball hitch in a loose friction fit, and may be secured to the ball in preparation for towing. An example is illustrated in FIG. 1.
Referring to FIG. 1, a side view is shown of a towing vehicle 10 towing a trailer 12 with a trailer hitch 14. It will be understood that the towing vehicle 10 may be any variety of vehicle known in the art, such as a truck, tractor or car, or any other variety of on-road or off-road vehicle, for example. Likewise, the principles of the present disclosure may be utilized with any variety of trailer 12 known in the art, such as camping trailers, boat trailers or cargo trailers, for example.
As is known in the art, the load from the trailer 12 may force the rear end of the towing vehicle 10 down and raise the front end of the towing vehicle 10 and thereby hitches may drag on the ground. Load equalizing systems, as discussed more fully below, have been used to distribute the load created by the trailer 12 on the towing vehicle 10 to thereby make the trailer 12 and towing vehicle 10 more level.
One of the biggest safety concerns with towing trailers is that the trailers may sway, leading to loss of control of the towing vehicle. A number of factors may contribute to sway, including: side winds, passing vehicles, quick lane changes, uneven roads and sudden stops. Some trailer hitches may not handle these situations well and may often exacerbate the sway problem making driving even more stressful and difficult.
Another common problem encountered when towing a trailer is “highway hop,” or the bouncing that often happens to trailers on uneven roadways. This problem may be caused by uneven weight distribution. With ordinary ball-type hitches, most of the trailer tongue weight may be carried on the back axle of the tow vehicle. This may raise the front end of the tow vehicle. The uneven distribution of weight may make steering control more difficult, especially during emergency situations. Weight distribution allows a trailer and tow vehicle to be level. Risks associated with driving a trailer without a weight distribution hitch may include loss of steering control, braking difficulties, and hitch dragging.
Some hitches include load equalizing systems utilizing spring arms or bars to distribute loads and allow the towing vehicle and trailer to remain level. One end of the spring arms may be attached under the ball hitch and hitch head. The spring arms may extend from the hitch head towards the trailer, and may be joined to the trailer tongue using chains and/or brackets. The end of the spring arms opposite the hitch head may be lifted or loaded to place an upward force on the hitch head to thereby equalize the load exerted on the trailer hitch. Various mechanisms are known for use in association with a trailer hitch to reduce side sway of the trailer as well as to equalize loads.
Some prior art embodiments of the brackets for joining the spring bars to the trailer tongue have been formed as rigid members. FIG. 2 illustrates an example of the prior art, which shows an enlarged view of the hitch 14 on a break-away view of the trailer 12, the trailer 12 typically includes a trailer tongue 16 extending at a forward end of the trailer 12. The trailer tongue 16 may comprise a frame member 17. A coupler 18 typically will be located on an end of the tongue 16 for receiving a ball 20 of the hitch 14, in a manner known in the art. The ball 20 typically will be disposed on a hitch head 22 which typically will be attached to the tow vehicle 10 through a connector 24. A spring bar 26 typically will be joined to the hitch head 22 at one end, and to the frame member 17 of the trailer tongue 16 at an opposing end portion using a bracket 28. Typically, two spring bars 26 will be used, one on each side of the trailer tongue 16.
The spring bars 26 may be configured to provide an upward force on the hitch head 22 to equalize the distribution of the load and allow the towing vehicle 10 and trailer 12 to be more level. The spring bars 26 may also be beneficial for reducing sway of the trailer 12.
Referring now to FIG. 3, a perspective view is shown of one embodiment of the hitch system, indicated generally at 14, in accordance with the principles of the present disclosure. It will be understood that the hitch system 14 may be attached to the tow vehicle 10 and trailer 12 as shown in FIG. 1. The hitch 14 will typically include the hitch head 22 for receiving the ball 20. The hitch 14 will typically include a connector 24 for attachment to a tow vehicle 10. The hitch 14 will typically include spring bars 26 for applying an upward force on the hitch head 22 as discussed above. Brackets 28 may be provided to join the spring bars 26 to frame member 17 of the trailer tongue 16, as shown most clearly in FIG. 4.
An orthogonal side view of the bracket 28 is shown in FIG. 4. The bracket 28 must include a fastening mechanism for attaching the brackets 28 to the trailer tongue 16. The fastening mechanism will typically include one or more attachment members 44 and one or more fasteners 46 for joining the attachment members 44 to the trailer tongue 16. The attachment members 44 could be plates. The prior art typically uses a single fixation point 45 between the attachment member 44 and a support member 48. A single fixation point allows for off axis loads to cause rotation 77 about the point, which greatly increases wear.
Referring also to FIG. 5, the bracket 28 typically also included the support member 48 for supporting the spring bar 26. One embodiment of the support member 48 will be formed of a rigid member having a substantially “L” shaped configuration. The support will include an upward extending portion 50 for being attached to the bracket 28, and a lateral extending portion 52 for receiving the spring arm 26 thereon. The upward extending portion 50 will include one or more openings 51 for adjustably attaching the support member 48 with respect to the bracket 28 in an upward and downward direction. The bracket 28 will also include an adjustment mechanism 54 for use in combination with the openings 51 for adjusting a position of the support member 48 with respect to the bracket 28 holding the support member 48 in place.
The adjustment mechanism 54 will include a fastening member 56, such as a pin. The adjustment mechanism 54 will also include a support receiver 58 for receiving the upward extending portion 50 of the support member 48 such that the support member 48 can be moved with respect to the receiver 58 as the support member 48 slides up and down in the receiver 58.
A drawback of the prior art brackets formed as rigid members is that the fastening member 56 may wear and enlarge the openings 51 such that the bracket 28 does not provide stabilizing support to the spring bars 26 relative to the tongue 16. This looseness or play can result in greater and greater inertial loads to be experienced within the system until the bracket 28 has experienced decreased clamping ability and will allow the spring bars 26 to swing back and forth like a pendulum.
With reference to FIG. 6 the areas of wear will be discussed. FIG. 6 is a cutaway view of a bracket 28 and the frame member 17 of the trailer tongue 16. As the fastening member 56 works within the hitch system it will experience loading cycles consistent with towing. The fastening member 56 experiences these cycles where the openings 51 and the fastening member 56 make physical contact (shown by the W) and wear occurs. In some instances the wear can enlarge the hole to such a degree that bracket 28 may have decreased clamping ability. FIG. 7 further illustrates an instance where the opening has enlarged to a degree that the fastening member 56 no longer provides a pressure fit but is bottomed out at point B. Without the pressure fit the cyclic loading begins to have an inertial component thereby magnifying the loads. The prior art is characterized by these several disadvantages and other disadvantages that may be addressed by the present disclosure. The present disclosure minimizes, and in some aspects eliminates, the failures of the prior art, by utilizing the methods and structural features described herein.
The features and advantages of the disclosure will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by the practice of the disclosure without undue experimentation. The features and advantages of the disclosure may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims.